Most of my “HDMI-DVI” adapters are female HDMI to male DVI. They’re intended to convert a DVI port on a PC to a HDMI port, allowing you to connect your HDMI monitor to “DVI” on the PC. However, what I wanted to do was a little bit backwards.
I wanted to connect a HDMI laptop/computer (common output, nowadays) to a monitor without HDMI, but with DVI. I knew that with a standard $1 male-male HDMI cable, I could connect the computer to the adapter. However, the other end of the adapter has pins for DVI-I dual link, but the monitor’s female end shows DVI-D dual link.
I looked at the pins on Wikipedia and deemed the side pins a bit unnecessary (“don’t care”), as they were for analog communication. I pulled the 4 square pins (C1-C5), but the plug still wouldn’t fit. I realized that the flat connector (C5) was a bit longer on the converter than the DVI cable I was using; I saw that it was analog as well, and pulled it out. and then it worked! I was able to hack my $2 HDMI-DVI adapter to work not as intended, given a few minutes of research and understanding. Of course, one could buy the correct converter from Monoprice, but shipping costs tend to be too much for one item, and sometimes you need a hack in the moment, instead of waiting a few days for shipping.
A year ago, I understood DVI-D vs DVI-I on video cards and how the DVI connector on video cards supported extra pins for analog input, and could be used with VGA monitors given a cheap, passive DVI-VGA converter found with every video card nowadays. Now I understand it just a bit more.